TS only wants us to be public for his brilliant idea. We are not supposed to interfere, we are just supposed to be public.
In my last posting I reacted on a posting by 'v4lve lover' that now has disappeared.
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I made some tube base adapters so I could use a cheaper Loctal tube in an Octal base, and even with that bigger form factor, space is a limiting factor.
If I was tackling this I think I would try and use something like a socket saver, but remove the heater pins. Then modify the adaptor so that there would be two wires exposed to connect a heater supply. Then a compact heater supply just has to be installed somewhere in the cabinet, and connected to the adaptor(s). Since the existing tube heater wiring would not have to be disturbed, and the new connections would be on top of the chassis, the risk should only be in getting the socket saver adapted ok.
If I was tackling this I think I would try and use something like a socket saver, but remove the heater pins. Then modify the adaptor so that there would be two wires exposed to connect a heater supply. Then a compact heater supply just has to be installed somewhere in the cabinet, and connected to the adaptor(s). Since the existing tube heater wiring would not have to be disturbed, and the new connections would be on top of the chassis, the risk should only be in getting the socket saver adapted ok.
There are plenty of PCL86 available, so I agree with idea PCL86+voltage doubler for Uff.
I try this solution in one of my amp, and it works great. I used 2m2/25V capacitors for 2pcs of PCL86, and it is really overload. I think that 1000u will be enough.
Caterpillar, if you want order from Conrad, and dont pay too much shipping, you can try contact SOS company in Kosice, they are Conrad party, so they are able to order and deliver to you stuff from there. I bought this way some items.
I try this solution in one of my amp, and it works great. I used 2m2/25V capacitors for 2pcs of PCL86, and it is really overload. I think that 1000u will be enough.
Caterpillar, if you want order from Conrad, and dont pay too much shipping, you can try contact SOS company in Kosice, they are Conrad party, so they are able to order and deliver to you stuff from there. I bought this way some items.
Quote from post #59: But how to get the bridge rectifier and capacitors in an adapter of reasonable size? Maybe by putting the voltage doubler in a little seperate box which is attached with a four prong cable to the than simple adapter so you can always find room for the voltage doubler in any radio?
I'd be amazed if there was not enough real estate in an old radio for a small self contained power supply. For instance, the old electrolytic can caps are generally surplus, so something that occupies the space of one of those would work.
An old wall wart could be a worst case solution, with the wire just plugged into a connector in the radio.
My questions in post #59 were rhetorical. I just refered to post #59 to show that this thread get's filled with proposals that already have been made earlier in this thread.
Then I guess you and I are on the same wavelength, which is more than can be said for his old radio, missing its output tubes?
Yes. It would look something like a single bias tester for noval tubes, but than with the cable (with four instead of two wires in it) to a small box with the voltage doubler Kay proposed and tested. Two of the wires come from pins 4 and 5 of the adapter, and the other two wires go to contacts 4 and 5 of the socket of the adapter.
So why TS keeps on insisting that this solution requires work on the radios themselves, stays a mistery to me.
So why TS keeps on insisting that this solution requires work on the radios themselves, stays a mistery to me.
That I don't understand.
I thought that you would need two wires for the AC to go from the adapter to the voltage doubler, and two wires for the DC to go from the voltage doubler back to the adapter. Something like this, you can plug into any radio with an ECL86. The only extra 'effort' is to place the small box with the voltage doubler somewhere in the radio (or any radio). Most of the time you can just hang it at the backplate, close to the socket. You have the radio (or any radio) opened anyway.
I thought that you would need two wires for the AC to go from the adapter to the voltage doubler, and two wires for the DC to go from the voltage doubler back to the adapter. Something like this, you can plug into any radio with an ECL86. The only extra 'effort' is to place the small box with the voltage doubler somewhere in the radio (or any radio). Most of the time you can just hang it at the backplate, close to the socket. You have the radio (or any radio) opened anyway.
Snip the heater pins of the socket saver, then adapt it to take two wires for a heater supply to the relevant pins. Then you are not constrained with the existing 6.3v supply, and you only need one solution for multiple tubes.
I did that, and I don't see any conflict with the suggestion. What were you thinking?
A pair of these APSG160ELL102MJB5S
and a pair of SBR10U45SD1-T would fit inside a "socket saver" type adapter (Delon).
The caps are rated for 20,000 hours @ 105c so they'll outlive the tube by a long margin.
No external PS needed, just plug it in to the ECL86 socket, and plug a PCL86 into that.
EDITED to change the diode from 1N4007 to SBR10U45SD1-T for less Vdrop ad change the drawing
and a pair of SBR10U45SD1-T would fit inside a "socket saver" type adapter (Delon).
The caps are rated for 20,000 hours @ 105c so they'll outlive the tube by a long margin.
No external PS needed, just plug it in to the ECL86 socket, and plug a PCL86 into that.
EDITED to change the diode from 1N4007 to SBR10U45SD1-T for less Vdrop ad change the drawing
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IN #87 OldHector suggested an additional PSU to heat the PCL86. As I've seen 14 Vdc units being already around, this also seems easily viable to me. But with some luck you'd also tweak a 12 Vdc unit for some higher output voltage.
Admittedly I'm a lazybones, especially when it comes to mechanical work. Hence, I'd prefer even in this case cutting the heater leads from the original socket and solder the PSU output leads to it instead of making a possibly fragile adaptor.
Best regards!
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@kodabmx: 1 mF capacitance might be not enough for the Delon circuit, as I found out that even 2.2 mF yield for just 12.8 Vdc. I'd suggest Schottky diodes in this case instead of 1N400x's. Anyway, one has to try and find out the suitable components in each individual instance.
Admittedly I'm a lazybones, especially when it comes to mechanical work. Hence, I'd prefer even in this case cutting the heater leads from the original socket and solder the PSU output leads to it instead of making a possibly fragile adaptor.
Best regards!
Edit:
@kodabmx: 1 mF capacitance might be not enough for the Delon circuit, as I found out that even 2.2 mF yield for just 12.8 Vdc. I'd suggest Schottky diodes in this case instead of 1N400x's. Anyway, one has to try and find out the suitable components in each individual instance.
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Good point with the diode. I've edited it to reflect the SBR10U45SD1-T super barrier diode. 12.8V is "close enough for government work" though...
SBR10U45SD1-T
SBR10U45SD1-T
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First of all I wanted to replace the original tube with something still manufactured. Maybe one day the PCL86 will become scarse and then what? back to the drawing board again.
As of now: 18.8.2020 unfortunately the ECL86 is not manufactured and no other tube is that is a candidate for replacement.
The ECC85 is still manufactured, and the EL84 aswell.
As of now: 18.8.2020 unfortunately the ECL86 is not manufactured and no other tube is that is a candidate for replacement.
The ECC85 is still manufactured, and the EL84 aswell.